Trends in mechanical circulatory support use and outcomes of patients with cardiogenic shock in Japan, 2010-2020: a nationwide inpatient database study

Abstract

Abstract Background/Introduction Little is known about the impact of the downgrade of guideline recommendations for intra-aortic balloon pump (IABP) use and the approval of the Impella in Japan, where IABPs have been enthusiastically used. Purpose This study aimed to describe the annual trends in the mechanical circulatory support (MCS) use and outcomes in patients with cardiogenic shock (CS) requiring MCS. Methods This was a retrospective cohort study using the Japanese Diagnosis Procedure Combination database, which contained administrative claims data and discharge abstracts from more than 1,500 acute care hospitals and covered approximately 90% of all tertiary emergency hospitals in Japan. Using the data from July 2010 to March 2021, we identified inpatients with CS requiring MCS. The primary outcome was in-hospital mortality. The secondary outcomes were the length of MCS, length of hospital stay, total hospitalization cost, major bleeding, ischemic stroke, continuous renal replacement therapy, and total blood transfusion volume during the hospitalization. The patients were stratified into three groups: (i) IABP alone, (ii) Impella alone, and (iii) extracorporeal membrane oxygenation (ECMO) regardless of IABP or Impella use. The patient characteristics and outcomes were reported by the fiscal year. Results Of the 160,559 eligible patients, 117,599 (73.2%) were identified as the IABP alone group, 1,465 (0.9%) as the Impella alone group, and the remaining 41,495 (25.8%) as the ECMO group. Of the overall 1,107 hospitals, IABP alone was used in 1,096 (99.0%), Impella alone in 120 (10.8%), and ECMO in 831 (75.1%). In-hospital mortality was 17.4%, 38.0%, and 68.3% in the IABP alone, Impella alone, and ECMO groups, respectively. The length of hospital stay was 32.6, 36.6, and 29.4 days and the total hospitalization cost was 4,522, 9,098, and 5,840 thousand yen in the IABP alone, Impella alone, and ECMO groups, respectively. All of major bleeding, ischemic stroke, and continuous renal replacement therapy were most prevalent in the Impella alone group and least prevalent in the IABP alone group. The prevalence of an IABP alone significantly decreased from 80.5% in 2010 to 65.3% in 2020 (P for trend <0.001). In contrast, the prevalence of an Impella alone significantly increased from 0.0% in 2010 to 5.0% in 2020, and the prevalence of ECMO significantly increased from 19.5% in 2010 to 29.6% in 2020. In-hospital mortality significantly increased from 29.3% in 2010 to 32.6% in 2020 in the overall patients with CS requiring MCS, but significantly decreased in those requiring ECMO from 73.7% in 2010 to 64.1% in 2020 (P for trend <0.001 for both). Conclusions There were significant annual changes in the patterns of MCS use and clinical outcomes in patients with CS requiring MCS.